What is the telephone dialing code / country code

Country phone code is using for calling between countries (international dialing). Most of countries has unique telephone dial prefix(country code).
Country phone codes starting with mark +, it's shortcut for IDD (International direct dialing). You can replace this mark with number. Most of countries use number 00. For international dialing, dial IDD of your country.
Some countries are divided to smaller areas with their own area prefix(area code).

System of dialing international code

International dialing to country with phone area codes
How to dial:

IDD country code you are calling from
Telephone dialing code for the country of destination
The telephone area code
Telephone number

International dialing to country without phone area codes
How to dial:

IDD country code you are calling from
Telephone dialing code for the country of destination
Telephone number

International calls are usually more expensive than national calls. Prices are higher because of connectivity length and in many cases call is transferring though several call providers. To save on phone calls, ask your mobile service provider about prices of international calls.

The system of national/local dialing call

In case of calling inside one country(national call). For national calling is not necessary dial IDD code or country code, just dial phone area code and phone number. In several countries is necessary add number zero 0 before area code.

What is IDD

IDD is (International direct dialing). This number is used for calling to another country (international call). Most of countries is using two zeros '00'. For internationa call dialing you are using IDD of your country. List of IDD codes you can find in table, or on country detailed information page.

What is the telephone dialing code / country code

System of dialing international code

The system of national/local dialing call

What is IDD

List of IDD country codes